1. Field of the Invention
The present invention relates to a device for diagnosing an organism and controlling the physiological state thereof, the devices operating by extracting the physiological state from the organism's pulse waves, diagnosing the condition of the organism and carrying out control of the physiological state thereof after taking into consideration the cyclic fluctuation which occurs naturally in the physiological state of that organism.
2. Description of the Related Art
Blood pressure, heart rate and the like are most typically used when diagnosing the condition of the circulatory system in the human body. Emphasis has conventionally been placed on such easily measured indicators as maximum and minimum blood pressures, blood pulse rate and the like which are obtained from the body, as one type of criterion for determining the state of the circulatory system and, in a wider sense, the condition of the organism. However, when carrying out a more specific diagnosis, it becomes necessary to measure circulatory parameters such as the viscous resistance of the blood vessel, compliance and the like. This will be explained further below.
The pressure waveform and blood flow rate at the proximal portion of the aorta and at the site of insertion of a catheter into an artery are frequently measured in order to measure physiological state indicators such as the circulatory parameters. For this purpose, a direct method of measurement, in which a catheter is inserted into an artery, or an indirect method employing ultrasound waves, may be applied. However, in the case of a method employing catheter insertion into an artery, it is necessary to subject the organism to an invasive and large device. On the other hand, while a method employing ultrasound or the like allows a non invasive observation of blood flow inside the blood vessels, this method is complicated by the fact that it requires training and, moreover, necessitates a large device to carry out the measurements.
As research on blood pulse waves has progressed, it has become clear that a variety of physiological conditions, not obtainable from blood pressure values and blood pulse rate alone, can be gotten by using a variety of methods to analyze blood pulse waveforms obtained from the human body. Diagnosis can then be made based on these physiological states. A “blood pulse wave” is the blood flow wave which is pumped out from the heart and propagates through a blood vessel. It is known that various medical information can be obtained by detecting and analyzing blood pulse waves. In particular, when measuring blood pulse waves at the periphery of an organism's body, the fingertip plethysmogram, the blood pulse wave of the radius artery, or the like are measured. However, there are a variety of other sites on the human body at which the blood pulse wave can be measured. In addition, there are a variety of forms which a blood pulse wave may take, three examples of which are shown in FIGS. 1A through 1C. The Ping mai, Hua mai and Xuan mai shown respectively in FIGS. 1A through 1C may be cited as representative blood pulse waveforms as categorized in Chinese medicine, a medical learning which is recognized in both the East and the West. “Ping mai” as used here indicates the waveform obtained from a healthy subject, with the blood pulse wave example shown in FIG. 1A measured in a 34 year old male test subject. As shown in the figure, a Ping mai is relaxed, and exhibits a constant rhythm without disruption. The Hua mai, on the other hand, is caused by an abnormality in the flow of blood in which the movement of the blood through the vessel becomes extremely smooth due to a mammary tumor, liver or kidney ailment, respiratory ailment, stomach or intestinal ailment, inflammation, or some other illness. The blood pulse wave shown in FIG. 1B is a typical example of a Hua mai, and was taken from a 28 year old male. As shown in the figure, the waveform of a Hua mai exhibits a sharp, rapid rise, and then falls off immediately. The aortic notch is deep, while the peak in the subsequent relaxation period is considerably higher than Ping mai. On the other hand, a Xuan mai is caused by an increase in the tension in the walls of the blood vessels, and is seen in diseases such as liver and gall ailments, dermatological ailments, high blood pressure, and pain ailments. It is believed that tension in the autonomic nervous system causes the walls of the blood vessels to constrict, decreasing elasticity, so that the effect of the blood pulse movement of the pumped blood is not readily expressed, causing this phenomenon. A typical example of a Xuan mai is shown in FIG. 1C and was taken from a 36 year old male. As shown in the figure, the waveform of a Xuan mai rises violently, and does not fall off immediately but remains at a high pressure state for a fixed period of time. In the graphs shown in FIGS. 1A through 1C, blood pressure (BP) measured in mmHG is shown on the vertical axis, while time in sec is displayed on the horizontal axis.
As will be understood from the preceding discussion, by analyzing the waveform of the blood pulse wave and specifying whether the blood pulse wave is, for example, a Ping mai, Hua mai or Xuan mai, it becomes possible to determine the specific ailment, or provide a diagnosis of the patient's condition. It has not been the conventionally practice to carry out qualitative evaluations incorporating this point, however.
Further, as will be explained in greater detail below, the human body's physiological state fluctuates according to a regular rhythm, repeating these rhythms on daily, monthly or annual cycles. This characteristic applies as well to the various indicators of physiological state which can be obtained from the blood pulse wave. Accordingly, if diagnosis and control of an organism's physiological state is carried out without taking into consideration these cyclic fluctuations, then the diagnosis and control of the physiological state are meaningless. However, because a small device able to continuously measure physiological state throughout the daily activities of an organism has not been available previously, it would seem that these cyclic variations in physiological state have not been taken into consideration in the diagnostic technology employed until now.